Aprons have been formed from a wide variety of materials, the function of the material being to absorb liquid or soiling substances which may be splashed upon the apron, or to repel liquid, solid or other materials which might, but for the apron, soil the garment of the person wearing the apron. Accordingly, aprons are made of woven cotton cloth, paper, non-woven natural and synthetic materials, and the like. Some of the aprons are disposable, that is, meant to be discarded when soiled. The material from which the apron, whether disposable or not, is to be constructed, depends upon the particular requirements of its wearer. If the apron is to protect the garments of the wearer from a wide variety of soiling substances it is expected to be constructed from a suitably durable material; if the wearer is to be protected against acid and the like, the material of the apron is desirably made from acid-resistant material such as a synthetic resinous material, for example, a polyolefin, polyamide, and the like. Commonly preferred materials are polyethylene, poly(vinyl chloride), and nylon, but these materials are relatively more expensive than paper or cloth and therefore aprons made of such materials are not disposable. In fact, they are expected to be long-lived since they are easy to clean and durable. However, synthetic resinous materials in general, are highly susceptible to the propagation of slits or punctures however they are initiated. When a non-woven material such as a vinyl laminate (referred to herein as "vinyl" for brevity) is sewn, the piercing of the needle punctures and inherently weakens the vinyl so that stress tends to propagate the punctures. Thus, when a neck loop and waist-tying straps are sewn to a vinyl body member of an apron, as is conventionally done, repeated use of the apron causes the straps to tear away from the body member of the apron.
The vinyl laminate of non-woven poly(vinyl chloride) bonded to a woven cotton cloth fabric is a relatively new material which has been found peculiarly well-suited for the construction of an easy-to-care-for and durable apron. However, because of the relatively high cost of purchasing the material, and fabricating an apron from it, it is essential that the apron be adjustable, that is, it must fit a wide variety of body shapes and sizes. By "a wide variety of body shapes and sizes" I refer to male and female persons in the range from about 5 ft to about 6 ft tall, and weighing in the range from about 100 lb to about 200 lb. By "fit" I mean (i) that the apron must be worn comfortably by the wearer, supported in large part by the pelvic region of the body of the wearer, and (ii) the apron, when worn, must stay in position on the wearer without having to be constantly re-tied because the apron "rides up" or "rides down" due to its proclivity to slide without exertion of a force, on its straps or drawstrings, whether the apron is adjustable or not, and whether a single continuous drawstring or plural drawstrings are used.
Aprons are said to have been used since the beginning of recorded history, and because of their essential simplicity, there have been few improvements over the centuries which can be adjudged novel in this art. Such novelty as there is, usually derives from the special conditions under which the apron is to be used, and/or the particular materials from which it is constructed. In particular, adjustable aprons (also referred to as adjustable bib aprons) having an adjustable neck loop provided by a continuous tape or drawstring which serves both as a neck loop and waist-tying straps, and in which the draw string passes through folded corner portions of the body member of the apron are well known, being disclosed for example in U.S. Pat. Nos. 1,674,904 to Kemp, and 3,801,985 to Batt.
Kemp discloses an apron made from cheap, semi-stiff material in which open hems are provided by folding over and stitching extensions of the apron to form arm cut-outs. There is no provision for negating the propagation of punctures caused by stitching a material unknown at the time. A continuous drawstring provides an adjustable neck loop and also waist-tying straps. The open hems so formed, though arcuate, do not provide any reinforcing for wear resistance, nor is there any teaching as to the desirability of limited movement of the drawstring in the open hem, which limited movement is controlled by frictional engagement of the drawstring in the hem.
Batt discloses gluing an apron, rather than sewing it, to circumvent the problem of the propagation of punctures caused by sewing the material. In addition, for strength, Batt discloses straight-edged arm cut-outs deliberately so designed as to allow material in areas of the apron near where the strip exits from the body member to bunch up and form stress creases, so as to provide additional reinforcement against tearing of the material. Such bunching is deleterious to the vinyl laminate material used in the fabrication of my apron. Moreover, Batt is unconcerned with, and does not teach the desirability of obtaining substantial friction in the hem of the arm cut-out, between the continuous tape and the interior surfaces of the hem. Neither of the constructions of the prior art aprons meets the performance requirements of the expanded vinyl apron of this invention as will be be fully described hereinafter.